These are programs I wrote for an Apple II computer, which looks like this:

If you're interested in learning 6502 assembly language, I highly recommend Easy 6502. It's a fun, thoughtful, and joyful tutorial.

For Apple II-specific details, try the Technical Reference Manual -- it's suprisingly readable! There's also tons of great hobbyist content on the internet. There are definitely some quirks -- displaying stuff on the screen isn't as simple as it could be. But for the most part, it's a really small and elegant machine.